Sewing machine



April 30,1940. H, F, GRUMAN 2,199,171

SEWING MACHINE Filed April 12; 1937 ll Sheets-Sheet l g'wu can ton O Horace fi'rmwzg April 30, 1940. H. F. GRUMAN SEWING MACHINE Fil ecl April 12, 1'93? 11 Sheets-Sheet 2 I M W jforacefiz'ma,

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H. F. GRUMAN 2,199,171

SEWING MACHINE Filed April 12, 1937 ll Sheets-Sheet 4 ll (L I I l I l April 30, 1940. H. F. GRUMAN SEWING MACHINE 11 Sheets-Shet 5 Filed April 12, 19:57

April 30, 1940. H. F. GRUMAN 2,199, 7

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April 30, 1940. H. F. GRUMAN SEWING MACHINE Filed April 12', 1937 11 Sheets-Sheet 8 1 April 30, 1940. H F, 'R MAN 2,199,171

' SEWING MACHINE Filed April 12, 1937 ll Sheets-Sheet 9 April 30, 1940.

H. F'. GRUMAN SEWING MACHINE Filed April 12, 1937 l1 Sheets-Sheet 1O April 30,1940.

H. F. GRUMAN 2,199,171

I SEWING MACHINE Filed April 12, 1937 ll Sheets-Sheet 11 Patented Apr. 30, 1940 2,199,171

UNITED STATES PATENT OFFICE SEWING MACHINE Horace F. Gruman, St. Louis, Mo., assignor to Geoffrey Stevenson, Bufialo, N. Y.

Application April 12, 1937, Serial No. 136,466 48 Claims. (01. 112-177 This invention relates to new and useful im- Figure 9 is a detail side elevation showing the provements in sewing machines generally, alfabric guiding slot in the foot, though more particularly to a machine of the Figure 10 is a perspective view of the needle blind stitch type adapted especially for hemming driving mechanism,

operations. Figure '11 is a perspective view of the spreader 5 Heretofore, unsuccessful attempts have been driving mechanism, ,made on vertical needle machines to produce a Figure 12 is a perspective view of the looper flat ,overedge hem seam. In forming these prior driving mechanism, seams, the hem was folded back onto the body Figure 13 is an enlarged front elevation of the fabric and the needle was directed through all movable trimmer, 10

three fabric layers, and consequently when the Figure 14 is an end elevation thereof, seamed hem was returned to its normal position, Figure 15 is a rear view of the movable trima ridge of fabric which formed the hinge, exmer, tended along the line of seam. Figure 16 is a bottom plan view thereof,

15 One of the principal objects of this invention Figure 17is an enlarged perspective view of is to provide a blind stitch sewing machine for the work clamp, producing a flat overedge hem seam without Figure 18 is an enlarged perspective view of folding the hem back onto the body fabric. the chaining-off finger,

Another object of the invention is to provide a Figure 19 is an enlarged plan view of a hemmed 20 continuously rotatable ridge forming element for seam constructed by my invention, 20 projecting a ridge or node of fabric into needle Figure 20 is a cross section taken on the line penetrating position, whereby either all anchor 20-20 of Figure 19, stitches, or a predetermined combination of Figure 21 is a detail view showing more or less anchor and skip stitches may be formed. diagrammatically, the seam and the stitch form- Another object of the invention lies in the pros l n h n e bein sh wn at i ex- 25 vision of a chaining-off finger which is upwardly treme forward P t yieldable to accommodate the passage thereun- Figure 22 s a similar View bu ow the der of either cross seamsor thicker fabrics. spreader holding the needle thread 1001) Open With these and other objects in view which for entrance by t n dl ,30 will more fully appear, the nature of the inven- F u 3 s a s a w but sh w ng he ac tion will be more clearly understood by following leeper ad D in position t be t d y the description, the appended claims, and the needle,

several views illustrated in the accompanying Figure 24 is a detail P V showing a se m drawings. produced by a single thread,

I th drawings; Figure 25 is a detail plan view showing seam 35 Figure 1 is a front elevation of a sewing ma- Produced y three threads, chine constructed in accordance with my inven- Figure 26 is a s de elevation of a modified disc tion, construction,

Figure 2 is a left end elevation thereof, Figure 27 is an end elevation thereof,

Figure 3 is a rear elevation of the machine, Figure 28 is a detail plan View of a two e d 40 Figure 4 is a top plan view of the machine, vseam produced y y ac e W en using the Figure 5 is a vertical section taken on the line disc shown in Figures 22 and 7,

5-5 of Figure 4, t a Figure 29 is an enlarged side elevation of the Figure 6 is a vertical section taken on the line ridge forming d 5 5 of Figure 4, Figure 30 is a vertical section taken on the line 45.

Figure 7 is a horizontal section taken on the of Figure line 11 of Figure 1, v 1 Figure 31 is a horizontal section taken on the l Figures 7 and 7 are detail views showing the line 3 I- -3l of Figure 29, and driving connection for the feed lift rock shaft, Figure 32 is ap V ew show ng the edge of Figure 8 is an enlarged plan view of thepresser a superp fabric stitched to a b dy fabric.

foot, showing the ridge forming element, the Like reference numerals designate correspondtrimming mechanism, and the stitch forming ing parts throughout the several figures of the elements, drawings.

Figure 9 is an enlarged plan view of the foot My invention is directed to a blind stitch type 355 P v I. g U of sewing machine for forming a flat seam when joining superposed layers of fabrics by a line of elastic Z-thread overedge stitches.

The seam One of such seams as shown in Figure 19, includes a base layer A and a superposed layer B, the latter being preferably formed by a hem fold of the base layer and having an inner edge b. The line of stitches is formed by a needle thread C and a looper thread D. The needle thread is formed into a series of equally spaced loops 5 which are disposed in parallel planes arranged at right angles to the line of seam. The needle loops first pass under the inner edge 17 of the hem fold, then certain of said loops enter and emerge from the base layer A as at the points 6 to form anchor stitches, and then the bights l thereof are projected through the hem fold B, and the connecting portions 8 between the loops being exposed and lying along the side of and in parallelism with the inner edge b of the hem. Other needle loops will not enter the body fabric but will enter and pass upwardly through the hem to form skip stitches. However, it is possible by my invention to form all anchor stitches, or various combinations of anchor and skip stitches. The looper thread D is formed into a series of equally spaced loops Q which are disposed in parallel planes inclined to the needle loops 5. The looper loops 9 project through the bights "l of the needle loops and over the hem fold B and their bights it overlap the inner edge I) of the hem fold and are concatenated with the necks of the next adjacent needle loops, the connecting portions ll of the looper thread extending in a line which parallels the inner edge I) of the hem fold.

It will, therefore, be seen that the seam produced on my machine is fiat and is therefore devoid of the objectionable ridge of the seam heretofore made on a vertical needle machine.

The main frame The main shaft A main shaft 2i extends longitudinally along the upper arm 53 and across the standard l2 and is suitably journaled therein, the left hand end of the shaft extending across the recess l5 above the arm extension l6 and being journaled in the end wall ii, the arm extension i5 and the end wall i'l thus cooperating to form an extended bearing for the shaft.

The presser foot A horizontal presser foot F having an opening 22 is located below the arm extension and is rigidly secured thereto by spaced vertical arms 23, 2 -3.

The needle driving mechanism A horizontal needle shaft 25 is journaled in the spaced bearing lugs 59, 20 and is therefore located below and at right angles to the main shaft 2!, and directly above the opening 22 of the presser foot F. Attached to the forward end of the needle shaft and projecting towards the left thereof, is a needle arm 26 and attached to said arm is a curved needle 21 which carries the needle thread C. A rock arm 28 which is fixed to the needle shaft intermediate the bearing lugs ill, 29 is driven from the main shaft by an eccentric 29 fixed thereon in the recess 15 and a cooperating pitman Zldwhich extends upwardly through the recess 18. Thus, the needle will be reciprocated horizontally over the opening 22 once for each rotation of the main shaft, the forward or penetrating stroke of the needle being from left to right.

The looper and the driving mechanism therefor A looper 3i cooperates with the needle 27 to move a loop of. looper thread D into position for entrance by the needle, and a spreader 32, which in the present case is non-threaded, cooperates with both the needle and the looper to present a loop of the needle thread C to the looper. Thus a needle thread loop 5 will be projected through a looper thread loop 9 at the left hand side of the seam and a looper thread loop 9 will be projected through a needle thread loop 5 at the right hand side of the seam. It will also be noted that the stitch forming mechanism, as shown,

comprises the needle E'l', the loop taker or threaded looper 3i, and the loop taker or nonthreaded spreader 3t, and that they operate entirely above the presser foot.

The looper includes a beak 33 and an attaching shank 3:? arranged at substantially right angles to each other, the beak being provided with a thread eye 35 near its point and with a thread guide eye 36 at its heel. Fixedly mounted on the presser foot F in rear of the needle path, is a bearing 31 whichinclines upwardly towards the left, and journaled thereon is the hub 38 of a bell crank lever 39 which includes a forwardly extending inclined arm 40 to which the shank 34 of. the looper is attached by a screw 4|. The beak 33 of the looper projects downwardly to the left, and when the lever 39 is oscillated the looper will be reciprocated laterally in a slightly arcuate path across the line of seam and in an inclined plane. The looper in its forward movement travels from right to left and the path of travel inclines downwardly and rearwardly, the looper eye 35 being just below and in line with the needle travel when the looper is at the end of its stroke and when the needle is at the beginning of its forward or penetrating stroke. The other arm 62 of the bell crank lever 39 extends laterally and is pivotally connected to the forward end of an adjustable link 43, the rear end of the link being pivotally connected to a downwardly extending rock arm 44 of a bell crank lever 45 which includes a horizontal shaft t and an upwardly extending arm 4?, the shaft 46 being located in rear of the main shaft and journaled in the frame arm 53 and in the end wall I! thereof. main shaft and is connected to the arm 4'! by a pitman 39, the arm 4i being provided with-a segmental slot 56 and the pitman being adjustable along the slot and secured in an adjusted position by a clamping pin and nut assembly 5|. Thus, by means of this adjustment the stroke of the looper may be shortened or lengthened as desired. It will be noted that the bell crank lever 39 oscillates about an axis inclined to the vertical, and that the bell crank lever 45 oscillates about a horizontal axis.

A driving eccentric d8. is fixed to the The term backward and forward as applied respect to the front and the back of the machine.

The spreader andthe driving! mechanism therefor I The spreader 32 comprises a forwardly bowed beak which inclines downwardly from its horizontal shank 52 to its free end which terminates in a forwardly projecting V-shaped finger 53.

The shank 52 is fixed to the lower arm 54 of a lever 55 which is provided with an extendedhorizontal hub 56 journaled on a horizontal bearing pin 51 fixed to a forwardly extending wing 58 of a bracket 59 attached tothe horizontal arm extension l6 at the right of. the needle shaft 25, v

the wing 58 being laterally inclined towards the shaft to thereby position the longitudinal axis of thebearing pin 51, at an inclination to themain shaft 2|. The upper arm, 60' of the lever 55 is connected by a pitman 6| to an eccentric 62 fixed on the main shaft intermediate'the needle driving eccentric 29 and the looper driving eccentric 48. The spreader finger is thus reciprocated in a path which is inclined to the'line of feedand in a plane which is substantially at right angles to the general plane of the looper travel. The spreader finger thus moves forwardly and upwardly over the needle, starting from a point adjacent the presser foot opening 22 but 'on the right hand side thereof., and then moving forwardly to the left passing under the looper 3| which is then on its forward stroke, and in advance of the point'thereof.

Thus, as the needle begins its backward stroke, the spreader will pick up the needle thread loop and carry it forwardly into position to be entered by the looper, and the looper will then con- 'tinue itsforward stroke and position its'looper thread loop into position to be entered by the I 'needle during the next forward stroke of the latter.

It will be noted that the needle moves forwardly n'om the left hand side of. thepresser foot opening 22 and that the looper moves forwardly from the right hand side of said opening, whereasxthe spreader moves across both the needle path and the looper path.

The chaining-ofifinger In order for the machine to continue the formation of stitches, either at the end of a sea-med fabric or between a seamed fabric and a fabric which has just been inserted in the machine, I have provided the presser foot with a chaining- .ofi finger 63, the needle thread loops extending across and below the finger and the concatenated looper thread loops extending across and above the finger. This finger is positioned directly above the presser foot opening 22- and projects rearwardly from a laterally extending supporting shank 64 which is positioned in a transverse groove 65 formed in the upper face of the foot and on the right hand side of the opening, the finger extending across the path of the needle and the needlehaving its movement below the finger. The shank 64 is attachedto the front arm 66 of .a lever 61 which is fulcrumed as at 68 The rear arm 69 of the lever is urged upwardly by a coil spring 10 which is positioned between said rear arm and the foot.

The spring therefore functions to maintain the shank-54 seated in thegroove65 but-permits the tion 14.

fingerto be elevated against the tension of the spring when either cross seams or thicker fabrics are fed under the finger. It will be noted that the fulcrum 68 of the supporting lever 61 is 10- cated inrear of the free end of the finger 63 and; consequently when the finger is elevated the attaching end of the finger will be raised a greater distance than said free end, thus facilitating the enchained loops slipping off the finger.

The trimming mechanism It is desirable to trim the inner edge of the hem B prior to the hem being stitched to the body fabric A, and to provide means for turning the hem in advance of the trimming operation. To this end, the presser foot F is provided in front of the needle path, with an L-shaped opening comprising a longitudinal opening ll and a communicating lateral opening. The lateral opening is formed by a forwardly extending foot portion 13 and a rearwardly extending foot por- The under face of the portion 13 inclines downwardly and rearwardly, and the upper face of the portion'l4 inclines downwardly and rearwardly, said upperand lower faces conjointly forming a resultant rearwardly and downof a folder 'I'l which is secured to a bracket arm [8 removably mounted on the front wall of the lower frame arm Hi, the folder extending around the rearwardly projecting portion 14. The lon- 1 justably clamped therein by a screw 8|, the cutting edge ofthe blade preferably projecting slightlyinto the opening H and lying in parallelism with said opening. A horizontal movable blade or knife 82 cooperates with the ledger blade 19 to trim the upturned edge of the hem, the

movable blade being reciprocable across the rear end of the opening H, and being provided with a toe or extension 83 which is maintained in yieldable sliding contact with said ledger blade. The cutting edge of the movable blade inclines rearwardly towards the cutting edge of the ledger blade to provide a shearing cutting action between the blades, and the toe 83 is located atthe rear end of the cutting edge of the movable blade. The movable blade is removably attached to a holder 84 by a longitudinally extending clamp 85 and screw 86, the holder and the clamp being conjointly formed with a dovetailed groove for wardly inclined slot 15 for receiving the nose 16 receiving the blade. The heel of theholder. 84 is pivotally connected by a transverse pin 81 to the lower arm 88 of a supporting lever 89 which is fulcrumed on a horizontal stud or bearing 90 fixed to and extending forwardly from the bracket wing 58. The upper arm 9! of the lever is pivotally connected by a link 92 to an eccentric pin 93 fixed to the front end of the needle shaft 25. The holder 84 is provided with a rigid and rearwardly and terminates in close fitting relation to the toe 83.

From the foregoing it will be observed that both the needle and the movable trimmer blade are operated'from the needle shaft, that the needle moves from left to right during its forward or penetrating stroke, and that the movable blade moves from right to left during its cutting stroke.

The edge guide An edge guide G which is mounted on the front end of the presser foot for lateral adjustments, functions to guide the inner edge of the hem to the trimmer blades.

The work clamp Cooperating with the under face of the presser foot F to clamp the fabric against the thrust of the needle, is a horizontal work clamp 97 which is rigidly secured along its right hand edge to the upper end of a vertical shank or post 93 having a vertical slot 9B formed therein. The work clamp is provided with three parallel and longitudinally extending feed slots of equal length, there being two side slots 99, I and an interrupted intermediate slot comprising a front portion IOI, a rear portion I fil and an intermediate chaining-cif bridge MI". The intermediate slot IOI is centered with respect to the alined openings 22 and II in the foot, and the side slots 99, I00 are located on opposite sides of said openings. These slots extend from a point in front of the slot 1! to a point well in rear of the opening 22. The work clamp is supported on the lower frame arm I4 for vertical movements with respect to the presser foot, and to this end the shank 98 is supported for slidable movements between vertical guides I02, N3, the guide I02 being a part of the end wall !04 of said lower frame arm I4, and the guide I03 being removably mounted on said wall. The end wall I94 between said guides is provided with a vertical slot and fixed to the shank and projecting through the slot into the interior of the frame arm, is an abutment or arm I06 having a depending pilot stud I01. An adjusting screw I 68 is threaded upwardly into the bottom. wall I09 of the frame arm I4 directly below the stud I01, and a coil spring H0 is interposed between the stud and the screw for yieldably urging the work clamp upwardly and for normally retaining said clamp in yieldable engagement with the presser foot. In order to depress the work clamp 9'! against the tension of the spring 5 I 0, I have provided a treadle or kneepress operated chain HI which extends upwardly through an opening 5 H2 in the bottom wall I99 of the frame arm I4 and is connected indirectly at its upper end to the work clamp, as will be explained hereinafter.

The feeding mechanism Cooperating with the under face of the presser foot F to feed the fabric rearwardly are a 4-motion main feed dog I I3 and a d-motion differential feed dog I I4. The main feed dog i I3 includes two long side sections H5, H6 and a short intermediate section II! which operate in the rear portions of the feed slots of the work clamp. The side sections are disposed on opposite sides of the presser foot opening 22 and extend forwardly to a point slightly in front of the needle path, but the intermediate section is disposed wholly in rear of the needle path and in rear of said opening, The differential feed dog includes two long side sections IIB, II9 and a short intermediate section I20 which operate in the front portions of the feed slots in the work clamp. The side sections are disposed on opposite sides of the presser foot opening II and extend forwardly to a point slightly in. front of said opening, but the intermediate section I20 cooperates with the foot immediately in front of the opening 'II and its rear end terminates in front of the trimmer ledger blade I9. The side sections H5, H8 and H6, H9 of the feed dogs are arranged in overlapping relation for engaging the body fabric through the combined length of both dogs.

The differential feed dog I I4 is attached to the upper end of a vertically disposed differential feed bar I2I which is fulcrumed at its lower end as at I22 to the front arm I23 of a horizontal feed lift lever I24 which is fulcrumed as at I25 on the shank 98 of the vertically movable work clamp 37. Pivotally mounted on the rear arm I26 of the lever as at I21 is a slide block I28 which is slidably mounted in a forked rock arm I29. The arm I29 is fixed to and extends from a fed lift rock shaft I30 which is journaled in the rear portion of the lower frame arm I4. The shaft I30 is provided with a rock arm I 3| located within the frame arm I4 and this arm is oscillated from a horizontal counter shaft I32, which extends lengthwise of the arm and across the standard, by a pitman I33 which is pivotally connected at its lower end to the rock arm and has its upper end engageable with a driving eccentric I34 fixed to said counter shaft as shown in Figs. '7 and 7 The shaft I32 is driven from the main shaft 2| by a 1-to-1 gear coupling located within the standand 5 and comprises a driving gear I35 fixed to the main shaft, a driven gear I36 fixed to the driven counter shaft I32, and an intermediate gear or idler I31 journaled on the standard. Although I have specifically shown and described a gear coupling between the main shaft 2I and the counter shaft I 32, any other known mechanical driving means having a l-to-l ratio may be employed and I therefore use the term gear coupling in its broadest sense. Thus during each rotation of the main shaft the differential feed dog will be raised and lowered. Journaled in the lower frame arm I4 in rear of the rock shaft I30 is a differential feed travel rock shaft I38 which is actuated from the driven shaft I32 by means of a rock arm I39 located within the lower frame arm I4 and fixed to the shaft I38, and a pitman I49 which is pivotally connected as at I4I to said rock arm and has operative connection with the driven shaft through the medium of an adjustable'eccentric fixed to said driven shaft and indicated as an entirety by the numeral I42. Fixed to the left hand end of the rock shaft I38 is a rock arm I43 and a horizontal link I44 is pivotally connected atits rear end as at I45 to said rock arm and is pivotally connected at its front end to a stud or pin I46 fixed to the differential feed bar I2I. Consequently a back and forth movement will be imparted to the differential feed dog II 4 during each rotation of the main shaft, and by adjusting the eccentric I42 the feed stroke of the dog may be varied.

The main feed dog I I3 is attached to a forwardly and slightly downwardly inclined main feed bar I47. The front end of the bar is provided with a fork I48 which has sliding engagement with the pin I46 fixed to the difierential feed bar I 2| and consequently the front end of the main feed bar is supported by and moves upwardly and downwardly with said differential feed bar. The rear end of the main feed bar I41 ispivotally connected as at I49to a rock arm I50 fixed to a sleeve or tubular feed travel shaft II which surrounds the differential feed travel shaft I38. A rock arm I52 is fixed to the ,tubular'shaft I5I and this arm is oscillated from the driven counter shaft I32 by a pitman I53 which is pivotally connected as at I54 with said rock arm and has operative connection with the driven shaft through the medium of an adjustable eccentric fixed to said driven shaft and indicated a s an entirety by the numeral I55. Consequently a back and forth movement will be imparted to the main feed dog during each rotation of the main shaft, and by adjusting the eccentric I55 thefeed stroke of the dog may be varied,

1 From theforegoing, it will be seen thatboth feed'dogs are moved'upwardly and downwardly in unison, and that the feed travels of the dogs are independently adjustable.

In the operation of the feeding mechanism, let it be assumed that the differential feed bar IZI is beginning its upward stroke. The lever I24 is rocked about its fulcrum I25 and the feed bar is lifted until it engages the under face of the press'er foot. The lever I24 then shifts its fulcrum to the pin I22 and'consequently the original fulcrum I25 is moved downwardly taking the work clamp 91 therewith. This frees the fabric from its clamped, condition between the foot and the work clamp, and permits the feed dogs to func- 1 tion. At the end of the feed stroke, the original fulcrum is moved upwardly while the auxiliary feed bar is moved downwardly, whereby the work clamp willbe restored to its initial clamping position.

- The ridge forming element and the driving mechanism therefor,

Projecting upwardly through the front inter- ,anchor stitchespass entirel'ythrough the body.

fabric. Various combinations of anchor and skip stitches may be employed, such as, spaced anchor stitches with one or more intervening skip stitches. Inthe present instance, the ridge formingelement-H is constructed to effect the formation of an anchor stitch followed by three skip stitches, or, it canjbe adjusted to form all anchor stitches. By removably mounting this element, another element may be sub stituted for forming alternate fanchor and skip stitches. n 1

Located within the lower frame arm I4 is a rotary shaft I56 whose longitudinal axis lies in the vertical plane containing the needle path of movement. This shaft is journaledin spaced right and left bearings I51, I51 of alever arm I58 which is provided at its inner end with a,

transverse horizontalbearing I59 journaled' on a stud I 60 fixed to the front wall I5I of the frame arm I4. The outer or'left end portion of the shaft projects through the slot I05 of the end wall I04 of the lower frame arm I4 and through the vertical slot 918 of the shank 98 of the work support 91, and is provided at itsouter end with an inwardly extending counter bore I62 and a threaded bore I63; I The ridge forming element the same vertical'plane.

H, as shown in igs. 29'and 30, isin thenature of a star disc, and this disc is provided with an integral hub I64 which is received by the counter bore I62 and the hub is provided with an integral threaded pin or reduced extension I64? which is threadedly engaged in the bore I63 wherebythe disc may be readily removed. The

of the arms, and the leading edges I659, l66

I61 and I68 are disposed at'ac'ute angles to the diametric axes of. the arms, with the apices of the angles facing in the direction of the axis of the disc. A supplemental arm I68 is slidably mounted in a radial slot I69 formed in one face I of the arm I68, and is retained in any position of radial adjustment by a screwand slot con-- ripheries thereof, as shown by the dotted lines in Fig. 29; The discshaft I56 is pressed upwardly by aspring I1I located intermediate the su porting lever arm I58 and the'bottom wall I09 of the lower frame arm I4, and a manually operable screw I12 which is threaded downwardly into the top wall I13 of the lower frame arm I4 engages said lever arm and thereby enables the operator to vary the effective height of the disc relative to the needle path, the spring also functioning to permit the disc, to be automatically lowered when seams orthicker fabrics are fed through the machine. The disc shaft I56 is continuously rotated'from the counter shaft I32 by a driving connection which in thepresent instance includes a reduction gear coupling having a f te-1 ratio. Although, llhave specifically shown and described a gear coupling between these shafts, any other known mechanical reduction driving means may be employed and I therefore use the term reductiongear coupling in its broadest sense. To this end, a relatively small gear I14 which is fixed to the counter shaft I32 within the frame standard 5, drives a relatively large gear I15 which is loose on a stub shaft I16 fixed ,to the standard, the ratio being 2-to-l. Fixed to the gear I15 is a gear I11 of the same diameter as the gear I14, and this gear I11 drives a gear I18 which is loose on the counter shaft I32, the ratio of the gears I11, I16 being 1-.to-2. Fixed to the gear I18 is a gear I19and fixed to the disc "shaft I56 adjacent the transverse pivot I thereof. is'-a,'gear I 80 which is in constant mesh with the driven gear I19, the ratio of the gears I19, I80 Ibeingl-to-l, and consequently the disc will be rotated once during every four shaft I56 without any binding. The disc is rotated rearwardly in timed relation to the needle reciprocations whereby the peripheral portions of the disc arms will be successively positioned under the needle path substantially when the needle is beginning its forward stroke. Thus when the three arms I65, I66 and I8? are each positioned under the needle path, the needle will enter and emerge from the hem only and thereby form a skip stitch, and when the arm I68 is under the needle path the needle will enter and emerge from the body fabric and then enter and emerge from the hem and thereby form an anchor stitch.

Means for depressing the work clamp, the feed and the ridge forming element The upper end of the chain III previously described is connected to the free end of the lever arm I58 which supports the disc shaft I58. An interponent or bar I8I is mounted in a horizontal groove I82 formed in the shank 98 of the work clamp 91 for sliding movements across the vertical opening 98 of said shank, the interponent being formed along its upper edge with a recess I83. The interponent is retained in its groove or seat I82 by a fiat spring I84 attached to the shank 98, and the forward movement of the interponent is limited by a stop I85 carried thereby and engaging the rear edge of the shank. An opening I86 is formed in the forward end of the interponent for facilitating the forward movement thereof. The disc shaft I56 projects through the slot 98 above the interponent. When the interponent is in its forward position the recess I83 will not register with the slot 98 and consequently the disc shaft when depressed by the chain III will engage said interponent and thereby depress the work clamp together with the feed so as to permit the ready insertion of fabric in the machine, or removal therefrom. When, however, it is desirable to remove the ridge forming element H from the shaft I56 for the purpose of substituting another element, it is necessary to provide means for lowering the element below the presser foot and the work clamp in order for the element to clear the latter, and for this purpose the interponent IIII is moved rearwardly until the recess I83 therein registers with the opening 88 of the shank 88 of the work clamp. The operator can then depress the shaft It into the recess I83 and thereby position the disc H entirely below the work support whereby the disc may be readily removed from the shaft and another disc substituted thereon.

It will, therefore, be seen that the shaft I56 is substantially horizontal at all times; that'by having the fulcrum I58 located within the frame standard 5 the ridge forming element H will have a long radius and consequently the element will move in a substantially vertical plane when it is depressed by reason of cross seams passing thereover and the ridge of fabric will not become distorted by said movement; that the upper portion of said element normally projects upwardly through the opening IllI of the work clamp 91 and into the presser foot opening 22, and consequently when it is desired to remove the element from the shaft it is necessary to swing the shaft downwardly until the element clears the work clamp; that when the interponent I 8! is in its rearmost position, the shaft may be swung downwardly by a pull on the chain III without depressing the work clamp and the feed, and that when the interponent is in its foremost position the work clamp, the feed, and the element will be depressed by a pull on the chain to thereby permit the ready insertion of work into the machine or the removal of work therefrom.

The rotation of the disc H is timed with the needle reciprocations whereby a given arm of the disc will ridge the fabric immediately in advance of the needle penetrating the ridge, and the periphery of the arm is of sufficient length to support the ridge until the needle point enters the needle guide on the right hand side of the foot, whereby the ridge of fabric will be supported-by the needle until the latter on its return stroke leaves the fabric. By providing deep spaces between the arms as shown and described, the fabric will not be ridged during the feed action which occurs immediately after the needle is withdrawn from the fabric, and consequently the diiferential feed dog H4 will function at its maximum efficiency.

I may desire to substitute a non-threaded looper or spreader for the threaded looper 3| in which case both loop takers will cooperate with each other and with the needle to form an overedge flat seam employing only a single thread, as shown in Figure 24, or I may desire to substitute a threaded looper for the spreader 32 in which case both loopers will cooperate with each other and with the needle to form a flat overedge seam employing three threads, as shown in Figure 25.

In Figure 32, I have illustrated a flat seam which may be produced by my machine after first removing the trimming mechanism. In this figure, a fabric section X is superposed on a base section Y, and the edge of the former is joined to the latter by a line of blind stitches, preferably formed by the two threads C, D, as shown in Fig. 19.

As shown in Figures 26 and 27, a ridge forming disc I may be employed. The peripheral surfaces I8I .of the radial arms I88 are formed with circumferentially extending grooves I89 forming resultant spaced ridge forming shoulders I88, lill. The grooves are disposed in alinement and in the vertical plane containing the needle shaft 25. Consequently, the needle will enter and emerge from the base fabric at two spaced points prior to the needle moving upwardly through the hem fold. This results in each needle loop passing into and out of the body fabric at two spaced points I82, I92, as shown in Fig. 28, when anchor stitches are being formed.

It will be seen that the edge portion of the hem fold immediately after leaving the hemmer, is directed upwardly by the opening II and is then trimmed by the cooperating horizontal cutting elements '19, 82. The trimmed edge portion of the hem fold is then turned down against the body fabric by engaging the'bridge on the presser foot between the alined openings II and 22 whereby the entire trimmed hem fold will be positioned flat against the body fabric immediately prior to the same being engaged by the ridge forming element H. Immediately thereafter the hem fold will be joined to the body fabric by the line of blind stitches in which the needle thread loops first enter the body fabric and pass upwardly through the hem fold and are concatenated by a covering thread which is formed into loops overlying the trimmed edge of the hem fold. This produces an extremely fiat and covered hem fold. It will be observed by reference ridge forming element on the free end of this,

shaft in the manner illustrated in Figures 30 and '31 ofthe drawings, the ridge forming element may-be removed with facility without disturbing anism, the combination with'a horizontal presser foot having an opening, of means for projecting a ridge of body "fabric upwardly through the opening into needle penetrating position, and a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for horizontal reciprocations across the ridge'forming means, and two oscillatory loop takers cooperating'with each other and with the needle, said loop takers being each fulcrumed on an axis located in'rearof the needle path, one of said loop takers being fulcrumed on a horizontal axis. x 1

2. In a sewingmachin'e' stitch forming mechanism, the combination with a horizontal presser foot having an opening, of means for projecting a ridge of body fabric upwardly through the opening into' needle penetrating position, and a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for-horizontalreciproc'ations across the ridge forming meanspand two oscillatory loop takers cooperating with each other and with the needle, one of said loop takers being fulcrumed .on a vertically inclined axis located in rear of the needle path and the other loop taker being fulcrumed on a horizontal axis inclined to the needle path and located in rear of the needle path, the first mentioned loop taker moving in a path inclined to the needle path and the second mentioned loop taker intersecting the needle path.

3. In a sewing machine, the combination with a frame having a main shaftjournaled therein, of a horizontal presser foot fixed to said frame and provided with an opening, ridge forming means for projecting a ridge of fabric upwardly through the opening into needle penetrating position, an oscillatory needle shaft journal'ed on the frame above the foot and operatively connected with the main shaft, a needle carried by said path, and separate'drivin'g connections be tween the loop'takers and theimain shaft.

4. In a sewing machine, the combination with a frame having a main shaft journaled therein, of a horizontal-presser foot fixed to said frame and provided with an opening, ridge forming means for projecting a ridge of fabric upwardly through the opening into needle penetrating position,'an oscillatory needle shaft journaled on the frame above the foot and operatively connected with the main shaft, a needle carried by said needle shaft for reciprocations across said ridge forming means, a loop-taker fulcrumed on the foot'in rear of the needle'path for reciprocations ina path in front of and in a path diagonal to the needle path and movable downwardly across the ridge forming means to a point below the needle path, a' loop taker fulcrumed on a horizontal axis on the frame in rear of the needle path for reciprocations intersecting said needle path and movable'upwardly from a point in rear of the needle path to a point in front of the path of movement of the first mentioned loop taker, the fulcra of said loo-p takers being located on the side of the ridge forming means opposite the needle when the latter is atthe beginning of its forward stroke, and separate driving connections between the loop takers and the main shaft.

-5. In a sewingma'chine, the combination with a frame havinga main shaft journaled therein, of a horizontal presser foot fixed to saidframe and provided with an opening, I ridge forming means for p-ro'jecting a ridge of fabric upwardly through the opening into needle penetrating position, an oscillatory needle shaft journaled on the frame above' the foot and operatively connected with the main shaft, a needle carried by said needle shaft for reciprocations' across, said ridge formin'g'means, a bell crank lever fulcrumed on the presser foot in rear of theneedle path and including a forwardly extending arm, a loop taker mounted on .the forwardly extending arm for reciprocations in front of and in a path diagonal totheneedle path, driving connections between the other' arm of said bell crank lever and the main' shaft including a bell crank lever fulcrum'edo'n a horizontal axis, a loop taker ful-- crumed in rear of the needlepath for cooperation with the needle andwith the first mentioned loop taker, andmeans for'operating said second mentioned loop taker. Y i

6. In a sewing machine, the combination with a frame having a main shaft journaled therein, of a horizontal presser foot fixed to'said frame and provided with an opening, ridge forming means for projecting a'ridge of fabric upwardly through'the openinginto needle penetrating pos tion, an oscillatory needle shaft journaled on the frame above the foot and operatively connected "withthe main shaft, a needle carried by said needle shaft for reciprocations across said ridge forming means, a 'bell crank lever fulcrumed on the presser foot in rear of the needle path and including a forwardly extending arm, a loop taker'mounted onthe forwardly extending arm' for reciprocations-in frontof and in a path diagonal to the needle path, drivingconnections between the other arm of said bell crank lever and the' main shaft including a bell crank lever fulcrumed on ahorizontal axis, a loop taker fulcrumed on-th'e frame in rear of the needle path for cooperation with the needle and with the firstmentioned loop taker, and driving connections between'the'm'ain' shaft Y and the second mentioned loop taker.

7;"Iii asewing machine, the'icombination with a frame in cluding a standard and an arm ex tending'laterally from theupper end'thereof and terminating in'an arm extension and an end wall, of' a main shaft journa-led in said arm and having an end portion extending above the arm extension and journaled in said end wall, a hori zontal presser foot disposed below and fixed to said arm extension and provided with an .opening, means for projecting'a ridge of material up-' wardly through the openinginto needle penetrating position, athreadedneedle supported by said arm for horizontal reciprocations across said ridge forming means, two loop takers cooperating with each other and with the needle, and separate driving means for said loop takers including an eccentric fixed to the main shaft above the arm extension and operating connections between one of said loop takers and said eccentric.

8. In a sewing machine, the combination with a frame including a standard and an arm extending laterally from the upper end thereof and terminating in an arm extension and an end wall, of a main shaft journaled in said arm and having an end portion extending above the arm extension and journaled in said end wall, a horizontal presser foot disposed below and fixed to said arm extension and provided with an opening, means for projecting a ridge of material upwardly through the opening into needle penetrating position, a threaded needle supported by said arm for horizontal reciprocations across said ridge forming means, two loop takers cooperating with each other and with the needle, a lever fulcrumed on the foot and supporting one of said loop takers, a lever fulcrumed on the arm for supporting the other loop taker, and separate driving connections between said levers and the main shaft including separate eccentrics fixed to the main shaft above the arm extension.

9, In a sewing machine, the combination with a frame including a standard and an arm extending laterally from the upper end thereof and terminating in an arm extension and an end wall, of a main shaft journaled in said arm and having an end portion extending above the arm extension and journaled in said end wall,'a horizontal presser foot disposed below and fixed to said arm extension and provided with an opening, means for projecting a ridge of material upwardly through the opening into needle penetrating position, a threaded needle supported by said arm for horizontal reciprocations across said ridge forming means, a bell crank lever fulcrumed on the foot in rear of the needle path to swing about a vertically inclined axis and including a forwardly extending arm, a loop taker mounted on the forwardly extending arm for reciprocations in front of and in a path inclined to the needle path, driving connections between the other arm of the bell crank lever and the main shaft including an eccentric fixed to said i shaft above the arm extension, a lever fulcrumed intermediate its ends on the arm extension in front of the needle path to swing about a horizontal aids inclined to the needle path, a loop taker mounted on the lower arm of said lever for w reciprocations in a path intersecting the needle path, and driving connections between the upper arm of said lever and the main shaft including an eccentric fixed to said shaft above the arm extension. I

' 10. In a sewing machine, the combination with a frame including a standard and an arm extending laterally from the upper end thereof and terminating in an arm extension and an end wall, of a main shaft journaled in said arm and having an end portion extending above the arm extension and journaled in said end wall, a horizontal presser foot disposed below and fixed to said arm extension and provided with an opening, a horizontal needle shaft extending at an angle to the main shaft and journaled in said shaft extension above the opening, a needle carried by said needle shaft for oscillations across the presser foot opening, a loop taker supported by the arm. extension for cooperation with the a needle, separate eccentrics fixed to the main shaftv above the arm extension, and separate driving connections between the needle shaft and one eccentric and between the loop taker and the other eccentric.

11. In a sewing machine, the combination with a frame including a standard and an arm extending laterally from the upper end thereof, of a main shaft journaled in said arm, a horizontal presser foot fixed to the free end of the arm below the main shaft and provided with an opening, means for projecting a ridge of body fabric upwardly through the opening into needle penetrating position, a horizontal needle shaft journaled in the free end of the said arm above said opening, a curved needle carried by said needle shaft, driving connections between the main shaft and the needle shaft for reciprocating the needle across the ridge forming means from left to right in its penetrating stroke, a vertical lever fulcrumed intermediate its ends on the frame arm to swing about a horizontal axis, a spreader fixed to the lower arm of said lever, driving connections between the upper arm of the lever and the main shaft, a bell crank lever fulcrumed on said foot, a threaded looper fixed to said bell crank lever, and driving connections between the looper lever and the main shaft, the spreader engaging and spreading the needle thread loop into position for entrance by the looper, and the looper entering the needle thread loop and then moving the looper thread loop into position to be entered by the needle.

12. In a sewing machine, the combination with a frame, having a main shaft journaled therein of a horizontal presser foot fixed to said frame and provided with an opening, ridge forming means for projecting a ridge of fabric upwardly through the opening into needle penetrating position, an oscillatory needle shaft journaled on the frame above the foot and operatively connected with the main shaft, a needle carried by said needle shaft for reciprocations across said ridge forming means, a threaded looper fulcrumed on the foot in rear of the needle path for reciprocations in a path in front of and in a path diagonal to the needle path and operatively connected with the main shaft, a spreader fulcrumed on a horizontal axis located on the frame in rear of the needle path for reciprocations intersecting said path and operatively connected with the main shaft, the spreader engaging and spreading the needle thread loop into position to be entered by the looper, and the looper entering the spread needle thread loop and then moving the looper thread loop into position to be entered by the needle.

13. In a sewing machine stitch forming mechanism, the combination with a horizontal presser foot having an opening, of means for projecting a ridge of body fabric upwardly through the opening into needle penetrating position, a chaining-01f finger pivotally mounted on the foot and projecting rearwardly along the opening above the ridge forming means, means for yieldably retaining said finger against upward movement, and a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for horizontal reciprocations across the ridge forming means and under the finger, and two reoiprocatory loop takers cooperating with each other and with the needle for moving a thread loop over the finger into position to be entered by the needle.

14. In a sewing machine stitch forming mechanism, the combination with a horizontal presser foot having an opening, of means'for projecting a ridge body fabric upwardly through the open ing into needle penetrating position, a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for horizontal reciprocations across the ridge forming means, two reciprocatoryloop takers cooperating with each other and with the needle, a chaining-off finger projecting rearwardly along the'opening above the ridge forming means, a lever fulcrumed intermediate its ends on the foot for supporting said finger at its front end, and yieldable means interposed between the rear end of the lever and the foot for yieldably retaining the finger against upward movement.

I 15. In a sewing machinestitch forming mechanism, the combination with a horizontal presser foot'having an opening, of means for projecting a ridge of body fabric upwardly through the opening into needle penetrating position, a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for horizontal reciprocations across the ridge forming means, two reciprocatory loop takers cooperating with each other and with the needle, a chalning-ofi finger projecting rearwardly along the opening above the ridge forming means, a

lever fulcrumed on the foot for supporting said finger, and yieldable means interposed between the lever and the foot for yieldably retaining the finger against upward movement.

16. In a sewing machine stitch forming mechanism, the combination with a horizontal presser foot having an opening, of means for projecting a ridge of body fabric upwardly through the opening into needle penetrating position, a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for horizontal reciprocations across the ridge forming means, two reciprocatory loop takers cooperating with each other and with the needle, and a vertically yieldable chaining-off finger projecting rearwardly above the ridge forming means,

said needle having its path of movement under 4 the finger and one of said loop takers having its.

movement across and over said finger.

17. In a sewing machine, a horizontal presser reciprocations above the opening, a rotatable element mounted below the foot for projecting a ridge of fabric upwardly through the opening into needle penetrating position, "and means for imparting continuous rotary motion to said element.

18. In a sewing machine, the combination with a presser foot having an opening, of a main shaft, a stitch forming mechanism including a needle mounted for horizontal reciprocations above the opening and having driving connections with said shaft, a rotatable element mounted below the foot and provided with a plurality of peripheral portions arranged in tandem for successively projecting ridges of fabric upwardly through the opening into needle penetrating po-.

sition, and driving connections between the main shaft and the element for continuously rotating said element in timed relation to the needlereciprocations.

19. In a sewing machine, the combination with a presser foot having an opening, of a main shaft, a stitch forming mechanism including a needle mounted for horizontal reciprocations above the opening and having driving connections with said shaft, a rotatable elementmounted below the foot and provided with a plurality of peripheral portions arranged in tandem for successively projecting ridges of fabric upwardly through the opening into needle penetrating position} and driving connections including a reduction gear coupling between the main shaft and the element for continuously rotating said element in timed relation to the needle reciprocations, the number of rotations of the main shaft to one rotation of the element corresponding to the number of peripheral portions of the element.

20. In a blind stitch sewing machine, a horizontal presser loot having an opening, a stitch forming mechanism including a needle mounted for horizontal reciprocations above the opening, a rotatable element mounted below the foot and provided with a plurality of spaced radial arms having concentric peripheral portions for proecting a ridge of fabric upwardly through the opening into needle penetrating position, each arm having'a trailing edge disposed in parallelism to the diametric axis of the arm, and a leading edge disposed at an acute angle to said diametric axis with the apex of the angle facing towards the center of the element, the trailing edge of one arm meeting the leading edge of the next adjacent arm at a point located inwardly from the chord of the arc intersecting the diametric axis of said adjacent arms at the peripheries thereof, and means for imparting rotary motion to said element. l

' 21. In a sewing machine, the combination with a presser foot having an opening, of a main shaft, a stitch forming mechanism including a needle I mounted for horizontal reciprocations above the opening and having driving connections with-said shaft, a rotatable element mounted below the foot and provided with a plurality of spaced radial arms haw'ng concentric peripheral portions arranged in tandem for successively projecting ridges of fabric upwardly through the opening into needle penetrating position, each arm having a/trailing edge disposed in parallelism to the diametric axis of the arm, and a leading edge disposed at an acute angle to said diametric axis with the apex of the angle facing towards the center of the element, the trailing edge of one arm meeting the leading edge of the next adjacent arm at'apoint located inwardly from the chord of the arm intersecting the dia-- metric axis of'said adjacent arms at the peripheries thereof, and driving connections between the mainshaft and the element for rotating said element in timed relation to the needle reciprocations.

22. In a sewingmachine, the combination with a presser .foot having an opening, of a main shaft, astitch formingmechanism including a needle 'mounted for horizontal reciprocations above'the, opening and having driving connections withsaid shaft, a rotatable element mountedbelow the foot and provided with a plurality of spaced radial arms having concentric peripheral portions arranged in tandem for successively projecting ridges of fabric upwardly through the openinginto needle penetrating position, each arm having a trailing edgedisposed in parallelismto the diametric axis of the arm, and a leading edge "disposed at an acute angle to said diametric axis with the apex of the angle facing towards the center of the element, the trailing edge of one arm meeting the leading edge of the 

